Coeliac disease in children with Type 1 diabetes mellitus: the effect of the gluten-free diet

PATIENTS AND METHODS

We assessed the frequency of coeliac disease in 281 children with Type 1 diabetes and the effect of gluten-free diet (GFD) in newly diagnosed cases. Serological screening was performed using anti-gliadin and anti-endomysium antibodies. Data were obtained about clinical symptoms, height and weight-for-height.

RESULTS

A small intestinal biopsy was recommended to 18 patients (6.4%) with positive serological results and 12 children agreed. Nine of them had coeliac disease. Three out of nine coeliac children complained about gastrointestinal symptoms. On a GFD, the symptoms disappeared in two patients. Iron-deficiency anaemia was present in four subjects and disappeared in the three patients who accepted the GFD. In three patients (33%), coeliac disease was asymptomatic. Height and weight-for-height were in the normal range for all patients. For well-complying patients, there was a significant increase in height standard deviation at diagnosis and on follow-up (-0.28 vs. +0.35) (P = 0.03). Changes in weight-for-height were not significant (-4.0% vs. +1.4%) (P = 0.28). There was a trend to an improvement in HbA(1c) (8.0 vs. 7.3%) (P = 0.05).

CONCLUSIONS

Serological screening is effective. There is a therapeutic benefit for some screening-detected patients, but confirmatory studies are needed.

Enhanced expression of group IIA secreted phospholipase A2 by elevated glucose levels in cytokine-stimulated rat mesangial cells and in kidneys of diabetic rats

BACKGROUND

Group IIA secreted phospholipase A2 (sPLA2-IIA) has been implicated in various inflammatory processes including the kidney. Previously it has been shown that potent proinflammatory cytokines such as interleukin 1beta (IL-1beta) increase sPLA2-IIA expression and secretion in rat mesangial cells.

AIM

The present study examines the effects of glucose on sPLA2-IIA regulation in interleukin-1beta (IL-1beta) treated mesangial cell cultures and in diabetic kidneys of Sprague-Dawley rats.

MATERIALS AND METHODS

Rat mesangial cells were grown either in low glucose (5.55 mM D-Glucose) or high glucose (25 mM) conditions followed by assessment of sPLA2-IIA transcription, expression and secretion after 24 h. The model of streptozotocin induced diabetes mellitus in Sprague-Dawley rats was used for the in vivo experiments. Diabetic kidneys where examined for sPLA2-IIA-mRNA and -protein expression as well as IL-1beta-levels at 2, 4 and 6 weeks after induction of diabetes mellitus.

RESULTS

Increased concentration of glucose had a weak, but significant stimulatory effect on sPLA2-IIA expression, which was markedly up-regulated (2-3-fold) in IL-1beta treated mesangial cells compared to the levels obtained in low glucose medium. Concerning the underlying mechanism, we found that high concentration of glucose increased the activity of the rat sPLA2-IIA-promoter, whereas mRNA stability was not affected. Furthermore, the in vivo experiments revealed a marked up-regulation of sPLA2-IIA mRNA and protein in the diabetic rat kidneys 2 - 4 weeks after induction. Since the strong up-regulation of sPLA2-IIA in vitro under high glucose conditions occurred mainly in presence of cytokine, we measured the levels of IL-1beta in diabetic kidneys by ELISA. We detected rat IL-1beta only in diabetic, but not in control rat kidneys.

CONCLUSIONS

The changes of sPLA2-IIA expression under increased glucose concentrations as well as in diabetic rat kidneys suggest a function of this enzyme as an acute phase protein providing lipid autacoids that may contribute to early changes in the course of diabetic nephropathy.

gp91phox-Containing NADPH Oxidase Mediates Endothelial Dysfunction in Renovascular Hypertension

Background— Isoforms of the NADPH oxidase contribute to vascular superoxide anion ( · O 2 − ) formation and limit NO bioavailability. We hypothesized that the endothelial gp91phox-containing NADPH oxidase is predominant in generating the O 2 − to scavenge endothelial NO and thus is responsible for the development of endothelial dysfunction.

Methods and Results— Endothelial dysfunction was studied in aortic rings from wild-type (WT) and gp91phox-knockout (gp91phox −/− ) mice with and without renovascular hypertension induced by renal artery clipping (2K1C). Hypertension induced by 2K1C was more severe in WT than in gp91phox −/− mice (158±2 versus 149±2 mm Hg; P <0.05). Endothelium-dependent relaxation to acetylcholine (ACh) was attenuated in rings from clipped WT but not from clipped gp91phox −/− mice. The reactive oxygen species (ROS) scavenger Tiron, PEG-superoxide dismutase, and the NADPH oxidase inhibitory peptide gp91ds-tat enhanced ACh-induced relaxation in aortae of clipped WT mice. Inhibition of protein kinase C, Rac, and the epidermal growth factor receptor kinase, elements involved in the activation of the NADPH oxidase, restored normal endothelium-dependent relaxation in vessels from clipped WT mice but had no effect on relaxations in those from gp91phox −/− mice. Relaxations to exogenous NO were attenuated in vessels from clipped WT but not clipped gp91phox −/− mice. After removal of the endothelium or treatment with PEG-superoxide dismutase, NO-induced relaxations were identical in vessels from clipped and sham-operated WT and gp91phox mice.

Conclusions— These data indicate that the formation of O 2 − by the endothelial gp91phox-containing NADPH oxidase accounts for the reduced NO bioavailability in the 2K1C model and contributes to the development of renovascular hypertension and endothelial dysfunction.

Expression of osteopontin (Eta-1) in Crohn disease of the terminal ileum

BACKGROUND

The causes of Crohn disease (CD) are still regarded as unknown, but impaired mucosal immunoregulation with activation of T-helper-1 (Th-1) cytokine responses is probably involved and may contribute to the morphological changes. We investigated a possible role of osteopontin (Opn) in the pathogenesis of CD. This glycoprotein has been suggested to be involved in the generation of Th-1-type immune responses; moreover, it carries anti-inflammatory activities.

METHODS

Ileal samples from CD patients--both actively inflamed and inactive areas as well as unaffected intestinal specimens from controls (normal ileum)--were investigated by Western blot analysis, immunohistochemistry and in situ hybridization.

RESULTS

In normal gut, Opn was found to be regularly expressed by plasma cells (CD 38) and a subset of lamina propria mononuclear cells (MNC) as well as by intestinal epithelial cells (IEC). In active CD, immunohistochemistry and in situ hybridization analysis revealed a loss of Opn expression by IEC adjacent to ulcerative lesions, whereas especially plasma cells (CD 38) in the vicinity of such lesions were found to express the molecule. In addition, a slight overexpression of Opn protein was found in metaplastic crypts. However, quantitative analysis of total Opn protein in the ileal mucosa of CD patients did not reveal any difference vis-à-vis control tissues.

CONCLUSIONS

The constitutive expression of Opn in normal gut indicates that it is involved in intestinal immune homeostasis. Downregulation of Opn expression in IEC might favour the disintegration of the epithelial barrier. The expression of Opn in lamina propria plasma cells could contribute to disease chronification, probably by affecting cell survival.

Construction of a combined sorghum linkage map from two recombinant inbred populations using AFLP, SSR, RFLP, and RAPD markers, and comparison with other sorghum maps

Sorghum [ Sorghum bicolor (L.) Moench] is an important crop in the semi-arid tropics that also receives growing attention in genetic research. A comprehensive reference map of the sorghum genome would be an essential research tool. Here, a combined sorghum linkage map from two recombinant inbred populations was constructed using AFLP, SSR, RFLP and RAPD markers. The map was aligned with other published sorghum maps which are briefly reviewed. The two recombinant inbred populations (RIPs) analyzed in this study consisted of 225 (RIP 1) and 226 (RIP 2) F(3:5) lines, developed from the crosses IS 9830 x E 36-1 (RIP 1) and N 13 x E 36-1 (RIP 2), respectively. The genetic map of RIP 1 had a total length of 1,265 cM (Haldane), with 187 markers (125 AFLPs, 45 SSRs, 14 RFLPs, 3 RAPDs) distributed over ten linkage groups. The map of RIP 2 spanned 1,410 cM and contained 228 markers (158 AFLPs, 54 SSRs, 16 RFLPs) in 12 linkage groups. The combined map of the two RIPs contained 339 markers (249 AFLPs, 63 SSRs, 24 RFLPs, 3 RAPDs) on 11 linkage groups and had a length of 1,424 cM. It was in good agreement with other sorghum linkage maps, from which it deviated by a few apparent inversions, deletions, and additional distal regions.

Direct measurement of OH radicals from ozonolysis of selected alkenes: a EUPHORE simulation chamber study

Reactions of ozone with alkenes can be a significant source of hydroxyl radicals in the atmosphere. In the present paper, the formation of OH radicals in the ozonolysis of selected alkenes under atmospheric conditions was directly observed. The experiments were carried out in the European photoreactor EUPHORE (Valencia, Spain). OH radicals were quantitatively detected by means of laser-induced fluorescence (LIF) using a new analytical instrument, which has been constructed on the basis of an existing setup already established in field studies. The OH radicals observed resulted directly from the reaction of ozone with the corresponding alkene. There was no indication that OH radicals were produced in the system by secondary processes. The experimentally observed concentration-time profiles of OH and ozone were excellently described by chemical modeling using explicit reaction mechanisms. The following OH yields were derived: 2,3-dimethyl-2-butene: (1.00 +/- 0.25); 2-methyl-2-butene: (0.89 +/- 0.22); trans-2-butene: (0.75 +/- 0.19); alpha-pinene: (0.91 +/- 0.23). In addition, the experiments carried out were modeled using the Regional Atmospheric Chemistry Mechanism (RACM), an established condensed chemical model applied in tropospheric chemistry. For 2,3-dimethyl-2-butene, 2-methyl-2-butene, and trans-2-butene the calculated concentration-time profiles of OH and ozone are in quite good agreement with the experimental data. However, in the case of alpha-pinene, the model fails for the simulation of OH due to the high grade of mechanism condensation, which results in a poor characterization of the primary reaction products.

Long-term results after microvascular decompression in essential hypertension

BACKGROUND AND PURPOSE

In 1998, 8 patients with severe, intractable arterial hypertension and MR tomography-demonstrated neurovascular contact of a looping artery at the root entry zone of cranial nerves IX and X, causing neurovascular compression, underwent neurosurgical decompression. The short-term results showed a normalization of blood pressure with a markedly reduced antihypertensive drug regimen in 7 patients. To determine the longer-term outcome concerning blood pressure and secondary organ damage after neurovascular decompression, we studied these 8 operated patients prospectively for a mean follow-up of 3.5 years after surgical intervention.

METHODS

Eight hypertensive patients who had undergone microsurgical decompression were monitored every 6 months after surgery to assess blood pressure (by 24-hour ambulatory pressure readings) and the need for antihypertensive medication. To evaluate secondary organ damage, echocardiographic assessment of left ventricular hypertrophy, fundoscopic assessment of hypertensive lesions, and analysis of renal function and proteinuria were done.

RESULTS

Three of the 8 operated patients remained normotensive in the long-term period with decreased antihypertensive medication. Two patients required gradual increases of antihypertensive medication after the first postoperative year, after which arterial blood pressure levels were 10% to 15% lower than preoperative levels. Three patients suffered serious cardiovascular and renal complications, with the incidence of lethal intracerebral hemorrhage in 1 patient and end-stage renal disease in 2 patients, of whom 1 experienced sudden cardiac death.

CONCLUSIONS

The long-term results verify that microsurgical decompression is a successful alternative therapy in a certain subgroup of patients with arterial hypertension due to neurovascular compression. However, the relevance of the looping artery in the other cases, who did not improve, is not clear. Prospective studies to elucidate the pathophysiological role of neurovascular abnormalities and arterial hypertension are needed.

Age- and stage-specific regulation patterns in the hematopoietic stem cell hierarchy

The molecular mechanisms that regulate self-renewal and differentiation of very primitive hematopoietic stem and progenitor cells in vivo are still poorly understood. Despite the clinical relevance, even less is known about the mechanisms that regulate these cells in old animals. In a forward genetic approach, using quantitative trait linkage analysis in the mouse BXD recombinant inbred set, this study identified loci that regulate the genetic variation in the size of primitive hematopoietic cell compartments of young and old C57BL6 and DBA/2 animals. Linked loci were confirmed through the generation and analysis of congenic animals. In addition, a comparative linkage analysis revealed that the number of primitive hematopoietic cells and hematopoietic stem cells are regulated in a stage-specific and an age-specific manner.

Multiple adenomas and hepatocellular carcinoma in a renal transplant patient with glycogen storage disease type 1a (von Gierke disease)

We report on a 42-year-old female patient with glycogen storage disease type 1a (von Gierke disease, GSD 1a) who developed hepatic adenomas and finally a hepatocellular carcinoma 10 years after renal transplantation. The tumor was resected; however, the patient died 6 months later as a result of fulminant carcinoma recurrence. In patients who have GSD 1a with terminal renal failure, combined liver and kidney transplantation may be considered at an early stage of the disease.

Expression of multidrug resistance P-glycoprotein in kidney allografts from cyclosporine A-treated patients

BACKGROUND

The multidrug resistance (MDR) gene product P-glycoprotein (P-gp) is a transmembrane efflux pump for hydrophobic, potentially toxic compounds, including the immunosuppressant cyclosporine A (CsA). We have previously shown that CsA increases P-gp expression in proximal tubule and endothelial cells in vitro. The aim of the present study was to investigate the in vivo relevance of these observations in renal allograft biopsies from CsA-treated patients.

METHODS

P-gp expression was determined by immunohistochemistry of paraffin sections using two different monoclonal antibodies (UIC2 and MRK16). Biopsies were taken from CsA-treated renal transplant patients with different histopathological diagnoses (N = 79) and were compared with biopsies from normal human kidneys (N = 13) or with allograft biopsies from patients under a CsA-free immunosuppression (N = 15). Moreover, biopsies from 10 donor kidneys before implantation and during rejection episodes ("zero biopsies") were investigated.

RESULTS

P-gp expression in biopsies with acute tubular necrosis (ATN; N = 10) after CsA treatment was significantly higher in arterial endothelia, proximal tubules, and epithelial cells of Bowman's capsule (BC), whereas P-gp was sparsely induced in CsA nephrotoxicity (N = 19) compared with controls. Acute cellular (N = 30) and vascular rejection (N = 10) or chronic allograft nephropathy (N = 10) after CsA was associated with strong P-gp expression in infiltrating leukocytes and increased P-gp expression in arterial endothelia, proximal tubules, and BC. In contrast, biopsies of patients treated with a CsA-free immunosuppression regimen did not show increases in P-gp expression compared with controls. Zero biopsies showed a weak, homogeneous, nonpolarized expression of P-gp in tubules and an increased expression of P-gp after CsA therapy in the brush border, arterial endothelia, and BC.

CONCLUSIONS

CsA treatment was associated with increased P-gp expression in parenchymal cells of kidney transplants with ATN, acute or chronic transplant rejection, but P-gp was not increased in patients with CsA nephrotoxicity. This indicates that CsA induces its own detoxification by P-gp and that inadequate up-regulation of P-gp in renal parenchymal cells contributes to CsA nephrotoxicity. Increased expression of P-gp in infiltrating leukocytes correlated with the severity of allograft rejection, suggesting that P-gp may decrease the immunosuppressive efficacy of CsA. Thus, individual differences in the P-gp induction response of CsA-exposed renal parenchymal cells and/or infiltrating leukocytes may predispose to either CsA nephrotoxicity or rejection, respectively.

Angiotensin II infusion increases plasma erythropoietin levels via an angiotensin II type 1 receptor-dependent pathway

BACKGROUND

Angiotensin-converting enzyme inhibitors (ACEIs) have been shown to lower hematocrit and erythropoietin (EPO), but a direct link between angiotensin II (Ang II) and EPO in humans has not been shown.

METHODS

Placebo or Ang II was infused for six hours in nine healthy male volunteers with and without blockade of the Ang II subtype 1 receptor (AT1R). EPO concentrations were measured 3, 6, 12, and 24 hours after the start of the infusion.

RESULTS

Ang II raised the mean arterial pressure by about 20 mm Hg. Consistent with the known diurnal variation, EPO levels rose significantly (P < or = 0.02) during the day in all groups. During Ang II infusion, EPO levels rose to significantly higher levels after 6 and 12 hours compared with placebo [9.9 +/- 3.5 vs. 7.2 +/- 3.1 mU/mL (3 h, P = NS); 16.9 +/- 4.5 vs. 8.8 +/- 3.7 mU/mL (6 h, P = 0.01); 17.0 +/- 8.6 vs. 11.1 +/- 4.7 mU/mL (12 h, P = 0.01)] and returned to baseline after 24 hours (7.9 +/- 3.8 vs. 10.6 +/- 8.6 mU/mL, P = NS). With AT1R blockade, blood pressure remained normal during Ang II infusion, and EPO levels were never significantly different from placebo [6.8 +/- 4.8, 10.5 +/- 5.6, 13.1 +/- 9.0, and 12.4 +/- 10.1 mU/mL at 3, 6, 12, and 24 h after infusion, respectively, P = NS].

CONCLUSIONS

Ang II increases EPO levels in humans. This increase requires the participation of AT1R.

Influence of diuresis on enzymuria

Urinary excretion of renal brush border enzymes may serve as an early marker of renal injury. However, the distinction between physiological and pathological levels remains controversial, since enzymuria is affected by physiological parameters. To clarify the influence of diuresis, we investigated the urinary excretion of alanine-aminopeptidase (AAP; EC 3.4.11.2) as function of diuretic state. 17 healthy volunteers of both sexes were subjected to protocols with sudden or prolonged water load preceded and followed by a thirst period. Urinary excretion of AAP was measured using an enzyme kinetic assay. As expected AAP excretion increased with urine flow, the increments diminished yielding an overall excretion pattern that resembled saturation kinetics. This function is described by a mathematical model. This model assumes, that AAP is released in proximal tubules at a constant rate and reabsorbed or inactivated in the distal tubule and collecting duct. Non-linear fits of the model equation to our data allowed two parameters, chi and mu, to be defined. Chi describes the rate of AAP release independent of urinary flow, and mu the ratio of distal tubular reabsorption or inactivation. If a substrate is not reabsorbed at all, mu approximates zero. Since mu fitted for AAP differed significantly from zero, this indicates reabsorption or inactivation of AAP in the distal nephron. Therefore, our study supports the theory of flow-dependent reabsorption or inactivation of AAP in the distal nephron.

Blood pressure control in essential hypertension and impairment of renal function with age

Hypertension has been recognized to be an important cause for the development of end-stage renal disease (ESRD). We assessed the quality of blood pressure control in 103 patients with essential hypertension and correlated renal function and age. Patients were stratified into three subgroups by their blood pressure level under current medication. Group 1 were hypertensive patients with normalized blood pressure (<140/90 mmHg, n = 25), group 2 patients with mild hypertension (140-159/90-99 mmHg, n = 43) and group 3 patients with moderate to severe hypertension (> 160/100 mmHg, n = 35). A negative correlation between age and creatinine clearance (Ccr) could be confirmed for patients of group 1 (correlation coefficient r1 = -0.56; p, < 0.01) and group 2 (r2 = -0.55; P2 < 0.001). Furthermore the regression coefficient (m) of decline in C(Cr) versus age was higher in group 2 patients (m2 = -1.83) than in group 1 (m1 = -1.30). In group 3 we found no correlation of renal function with age, indicating that age may not be the leading variable. Patients in group 1 were all within normal limits of age adjusted Ccr, but 12% in group 2 and 23% in group 3 had impaired C(Cr). Furthermore proteinuria was found to be 20% (group 1), 26% (group 2) and 31% (group 3). This analysis provides further evidence of the importance of blood pressure control in essential hypertension to preserve renal function.

Effects of continuous haemofiltration vs intermittent haemodialysis on systemic haemodynamics and splanchnic regional perfusion in septic shock patients: a prospective, randomized clinical trial

BACKGROUND

Parameters of splanchnic regional perfusion, like intramucosal pH (pHi) and pCO(2) (pCO(2)i), may predict outcome in septic shock patients. Continuous venovenous haemofiltration (CVVH) has been considered beneficial in haemodynamically unstable septic shock patients. In a prospective, randomized, clinical study, we investigated whether CVVH, in comparison to intermittent haemodialysis (IHD), is able to improve splanchnic regional perfusion in critically ill patients.

METHODS

Thirty septic shock patients with acute renal failure were randomized to either CVVH (n=20) or IHD (n=10) groups for renal replacement therapy. Patient characteristics at baseline were not different in terms of severity of illness (APACHE II scores), haemodynamics, and pHi/pCO(2)i values. Systemic haemodynamics, oxygen transport variables, and splanchnic regional perfusion parameters were measured at 0.5, 2, 4 and 24 h after initiation of renal replacement therapy. There were no major changes in vasopressor support throughout the 24-h study period.

RESULTS

In contrast to IHD, CVVH caused a decrease in heart rate (-3+/-11 vs +9+/-8/min, P<0.01) and an increase in systolic blood pressure (+12+/-1 vs -5+/-17 mmHg, P<0.05) after 2 h. After 24 h, increased systemic vascular resistance was found in the CVVH group in comparison with the IHD group (+312+/-755 vs -29+/-89 dyne/cm(5), P<0.05) and was accompanied by a decrease in cardiac output (-1.54+/-1.4 vs -0.25+/-0.9 l/min, P<0.01). However pHi values remained constant throughout the 24-h study period in both groups and were not different between the groups (CVVH 7.19+/-0.1 vs IHD 7.19+/-0.1, n.s.) as did the pCO(2)i values (CVVH +7+/-17 vs IHD 0+/-15 mmHg, n.s.) and pCO(2) gap values (CVVH +6+/-15 vs IHD +5+/-12 mmHg, n.s.).

CONCLUSIONS

Despite different changes of systemic haemodynamics between CVVH and IHD, CVVH did not improve parameters of splanchnic regional perfusion like pHi, pCO(2)i or pCO(2) gap in septic shock patients.

Monocyte chemoattractant protein-1 and macrophage infiltration in hypertensive kidney injury

BACKGROUND

We investigated whether monocyte chemoattractant protein-1 (MCP-1) is expressed in hypertensive nephrosclerosis, and tested the effect of angiotensin II type 1 receptor blockade on MCP-1 expression and macrophage (MPhi) infiltration.

METHODS

Rats with two-kidney, one-clip (2K1C) hypertension with and without treatment with the angiotensin II type 1 receptor antagonist valsartan (3 mg/kg/day) were studied. In these animals as well as in spontaneously hypertensive rats (SHR), stroke-prone SHR (SHR-SP), hypertensive mRen-2 transgenic rats (TGR), and respective control strains, MCP-1 expression in the kidney was investigated by Northern and Western blots and by immunohistochemistry. Glomerular and interstitial MPhis were counted.

RESULTS

In the nonclipped kidney of 2K1C rats, MCP-1 expression was elevated at 14 and 28 days when significant MPhi infiltration was present. MCP-1 was localized to glomerular endothelial and epithelial cells, interstitial and tubular cells, MPhis, and vascular smooth muscle cells. A similar pattern of MCP-1 staining was present in TGR kidneys, whereas MCP-1 expression was not increased in SHR and SHR-SP. Valsartan reduced but did not normalize blood pressure, blocked the induction of MCP-1 protein in 2K1C kidneys, and decreased interstitial MPhi infiltration significantly.

CONCLUSION

MCP-1 expression is increased in angiotensin II-dependent models of hypertensive nephrosclerosis and is temporally and spatially related to MPhi infiltration. The angiotensin II type 1 receptor mediates the induction of MCP-1.

Effect of angiotensin II infusion with and without angiotensin II type 1 receptor blockade on nitric oxide metabolism and endothelin in human beings: a placebo-controlled study in healthy volunteers

BACKGROUND

Angiotensin II has been shown to induce the synthesis of endothelium-derived relaxing factor nitric oxide (NO) and endothelin in vitro. In human beings, to our knowledge, no data on NO release in response to angiotensin II and on the influence of angiotensin II type 1 receptor blockade have been published.

METHODS

In a placebo-controlled study in nine healthy volunteers, angiotensin II was administered intravenously for 6 hours with and without pretreatment with valsartan, a specific angiotensin II type 1 receptor antagonist. NO (NO2 + NO3) and endothelin plasma concentrations, clearance values for inulin and paraaminohippuric acid and NO (NO2 + NO3) excretion in urine were determined.

RESULTS

During angiotensin II infusion NO plasma concentrations remained unaltered compared with placebo after 3 hours: 6.66 +/- 5.49 versus 5.56 +/- 3.09 micromol/L (P = ns) but increased after 6 hours: 18.36 +/- 20.02 versus 7.13 +/- 3.87 micromol/L (P < .04). The same was noted after pretreatment with valsartan: 7.61 +/- 5.69 versus 5.56 +/- 3.09 micromol/L (P= ns) after 3 hours, and 21.70 +/- 11.51 versus 7.13 +/- 3.87 micromol/L (P = .02) after 6 hours. In urine fractional NO excretion decreased after angiotensin II infusion: 0.87 +/- 0.72 versus 0.95 +/- 0.71 (P = .5) during the first 3 hours, and 0.44 +/- 0.39 versus 0.78 +/- 0.43 (P = .01) during the following 3 hours. After valsartan pretreatment the decrease in fractional urinary NO excretion began earlier: 0.40 +/- 0.15 versus 0.95 +/- 0.71 (P = .04) during the first 3 hours, and 0.17 +/- 0.11 versus 0.78 +/- 0.43 (P = .01) during the following 3 hours. Endothelin plasma concentrations showed no difference after angiotensin II infusion with or without valsartan.

CONCLUSIONS

Our observations demonstrate for the first time that angiotensin II increases NO plasma concentrations in human beings and that this response is not mediated by angiotensin II type 1 receptor. In spite of increased NO plasma levels, urinary NO excretion decreased. Endothelin plasma levels remained unchanged during angiotensin II infusion.

The cooccurrence of different biflavonoid types in Pilotrichella flexilis

From Pilotrichella flexilis various flavonoids have been isolated. This species contains in contrast to P. cuspidata not only 3',3'''-binaringenin and related compounds, but also some hitherto unknown biflavonoids based on eriodictyol and aureusidin. The structures of two new compounds are elucidated spectroscopically. Possible causes for the differences of the flavonoid patterns between the two species of the genus Pilotrichella are discussed.

Triflavones and a biflavone from the moss Rhizogonium distichum

From gametophytes of Rhizogonium distichum have been isolated the biflavone dicranolomin and five triluteolins. Two of the triluteolins, which were named rhizogoniumtriluteolin and distichumtriluteolin, were new compounds; their structures have been elucidated spectroscopically.